Railway air-brake.



PATENTED AUG. 23, 1904.

P. 'JAcoBsom RMLWAY Am BRAKE.

APPLICATION FILED JAN. 16, 1904.

2 SHEETS-SHEET 1.

N0 MODEL.

Mm-MU VPA'IEN'ID AUG. 23, 1904.

1% JAGOBSON.

RAILWAY AIR BRAKE.

APPLIATIOH FILED JAN. 16. 1904.

2 SHEETS-SHEET 2;

'NO MODEL,

UNITED. STATES Patented August 23, 1904.

PATENT OFFICE.

PETER JACOBSON, OF MILWAUKEE, VVISGON SIN.

'RAlLwAY AIR-BRAKE.

' SPECIFICATION forming part of Letters Patent No. 768,371, dated August 23, 1904.

Application filed January 16, 1904. Serial. No. 189,310. (No model.)

T0 /tZZ whom, it may concern:

Be it known that I, PETER JAooBsoN, a citizen of the United States, and a resident of Milwaukee, in the county of Milwaukee and State of Wisconsin, have invented certain new and useful Improvements in Railway Air- Brakes; and I do hereby declare that the following is a full, clear, and exact description thereof.

My invention consists in certain peculiarities of construction and combination of parts hereinafter particularly set forth with reference tothe accompanying drawings and 'subsequently claimed, the object of said invention being to improve the mechanism disclosed in my Patent No. 735,981, of August 11, 1903, and to provide simple, economical, and efficient automatic slack-adj usters for air-brakes of railway-cars.

Figure 1 of the 4drawings represents a plan view of railway-car air-brake mechanism, partly in horizontal section vand organized in accordance with my invention for automatic slack adjustment; Fig. 2, a view of a portion of the mechanism, partly broken away and in transverse section; and Eig. 3, a partly-sectional view of a detail of said mechanism, this view being indicated by line 3 3 in the second figure.

Referring by letter to the drawings, A indicates a railway-car air-brake cylinder, B the cross-head of the piston that plays in the cylinder, and C D the connected brake-rod levers that are respectively in pivotal connection with said cylinder and cross-head.

Substituted for the ordinary tie-rod connection between the levers C D is a turnbuckle comprising a rod E, the ends of which are screw-threaded one to the right and the other to the left. These screw-threaded ends of the rod engage screw thread inside of hollow stems E G, that have jaw ends in pivotal connection with the aforesaid levers, and to eX- elude moisture and dirt from said stems their inner ends are associated withgpacking and caps to form stufng-boxes around said rod.

.Rigid with the rod E between the stems F Gis a ratchet-wheel II, engaged by a pawl I in pivotal suspension in a rocker comprising a pair of plates J K, loose onsaid rod and connected by upper and lower bolts. The upper bolt is the pawl-pivot, and a spacer b is arranged on the lower bolt between the plates. The rod E takes the place of a sleeve set forth in the patent above noted, and the stems F Gr are necessarily hollow and interiorly screwthreaded to form an adjustable connection with said rod, the new construction being more economical and preferable in other respects than that in the patent aforesaid.

Like in my previous patent the upper eX- tension of the rocker-plate J is provided with an eye engaged by the curved and rounded end of a lever L on a pivot c between a suspended bracket M and an angular strap d, this strap being made fast at its ends to-said bracket. The other end of the lever is now made in the form of an elongated loop provided with an inner projection, herein shown as being a longitudinally-slotted segmental plate N, held by a set-screw e on the loop end of the lever between ears f of thesame; butl said lever may be made integral with a lug projecting into its loop. An extension of the pivot -pin g, connecting the piston cross-head B and brake-rod lever D, constitutes a striker that has play in the loop end of the lever L, and the projection N is in the outward path Aof the striker, its adjustment being in proportion to the desired initial play of the piston in the cylinder. In practice the predetermined brake-setting stroke of the piston in the cylinderA is equal to the distance between the striker g and projection N in the loop of lever L when the brake is off, the length of said stroke being increased in proportion to wear of the brakeshoes due to running application of said brake, and eventually said lever has sufcient pivotal play to effect a movement on the part of the rocker aforesaid that results in a slipping back of the pawl I into another notch of the ratchet-wheel I-I, rigid with the rod E of the turnbuckle connection between the brakerod levers. Due to swing of the lever L its loop is shiftedto the position shown by dotted lines in Fig. 1, the increased travel of the striker g. being likewise indicated in the same figure, and on back strokeof the'brake-piston there is draft of said striker in thevlever-loop,

IOO

the result being a rotary movement on the part of the turnbuckle-rod E to shorten the connection between the brake-rod levers, and thus compensate for slack that results from wear of the brake-slices. This automatic compensation for brake-shoe wear takes place from time to time in proportion to the frequency of running application of the brake mechanism, and the predetermined piston play in the brake-cylinder is always approximately the same, the variations at any time being too slight to effect the eiiicieney of said brake mechanism.

Having thus described my invention, what I claim as new, and 'desire to secure by Letters Patent, is-

l. A railway-car air-brake mechanism comprising hollow stems in pivotal connection with brake-rod levers and having inner end stuffing-boxes, a rod having its ends in right and left screw connection with the stems, a ratchet-wheel rigid on the rod, a rocker loose on said rod, a pawl carried by the rocker, in engagement with the ratchetwheel, and a rocker-actuating lever cooperative with the piston cross-head of said mechanism.

2. A railway-car air-brake mechanism comprisinga turnbuckle-coupling between brakerod levers, a ratchet-wheel rigid with the rotary element of the turnbuckle, a rocker loose on said rotary element of said turnbuekle, a wheel-engaging pawl carried by the rocker, anda rocker-actuating lever having a yoke end provided with an inner projection in the outward path of a striker that has travel with the piston cross-head of said mechanism.

3. A railway-carair-brake mechanism comprising a turnbuckle-eoupling between brakerod levers, a ratchet-wheel rigid with the rotary element of the turnbuekle, a rocker loose on said rotary element oi said turnbuckle, a wheel-engaging pawl carried b v the rocker, and a rocker-actuating lever having a loop end provided with an adjustable inner projection in the outward path of a striker that has travel with the piston cross-head of said mechanism.

4. A railway-car air-brake mechanism comprising a turnbuckle-coupling between brakerod levers, a ratchet-wheel rigid with the rotary element of the turnbuckle, a rocker loose on said rotary element of said turnluiel\'le a wheel-engaging pawl carried by the rocker, a rocker-actuating lever having a loop end provided With an inner projection, and the piston cross-head pivot-pin of said mechanism extended to constitute a striker having travel in the loopend of the rocker-actuating lever to operate against the projection in the saine.

5. A railway-car air-brake mechanism comprising a turnbuckle-coupling between brakerod levers, a ratchet-wheel rigid with the rotary element of the turnbuckle, a roekerloose on said rotary element ol said turnlnickle, a wheel-engaging pawl carried by the rocker and a lever having a curved end loose in an eye of the rocker, its other end being in the form of a loop provided with an inner projection in the outward path of a striker that has travel with the piston cross-head of said meehanism.

In testimony that I claim the foregoing l have hereunto set my hand, at Milwaukee, in the county oi' Milwaukee and State oi \Vis cousin, in the presence of two witnesses.

P. JACOBSON.

Witnesses:

N. E. OLIrnAN'r, HUGO FAnL. 

